Laser Beam Tester for Laser Beam Timing and Location Determination, Corresponding System and Method

The present disclosure relates to laser beam testing or laser beam timing and location determination, respectively. In particular, the present disclosure relates to a laser beam tester for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame, a system comprising such a laser beam tester and a laser beam emitting device, and a method for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame.

Generally, in times of an increasing number of applications employing laser beam emitting devices, such as autonomous driving applications employing lidar (light detection and ranging) sensors, there is a growing need of a laser beam tester for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame, a system comprising such a laser beam tester and a laser beam emitting device, and a method for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame in order to verify correct functioning of said applications in a highly accurate and efficient manner.

U.S. Pat. No. 8,259,311 B2 relates to a system for determining a position by emitting a first laser beam by a laser source positioned in a reference system onto a detector and simultaneously detecting the first laser beam by the detector, thus defining an emission direction of the laser source. The detector has a segmented detection area comprising a plurality of discrete partial detection areas, each having a defined partial detection direction and at least two partial detection directions thereof being different. When detecting the first laser beam, an impingement point of the first laser beam on the detector is detected by means of at least one partial detection area, and when determining the incidence direction, said direction is derived from the at least one partial detection direction. The location of the detector relative to the laser source and the reference system is then determined using the emission direction and the incidence direction.

Disadvantageously, said system does not allow for laser beam testing or laser beam timing and location determination, respectively.

Thus, there is a need to provide a laser beam tester for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame, a system comprising such a laser beam tester and a laser beam emitting device, and a method for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame, wherein laser beam timing and location can be determined in a particularly accurate and efficient manner.

This is achieved by the embodiments provided in the enclosed independent claims. Advantageous implementations of the present disclosure are further defined in the dependent claims.

According to a first aspect of the present disclosure, a laser beam tester for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame is provided. Said laser beam tester comprises an optical receiver configured to receive the at least one laser beam in an observation area, and a processor being in communication with the optical receiver. The processor is configured to determine the corresponding scan timing of the at least one laser beam. Furthermore, the processor is configured to associate the corresponding time domain of the laser beam tester with the scan timing of the at least one laser beam. Advantageously, laser beam timing and location can be determined in a particularly accurate and efficient manner.

According to an implementation form of the first aspect of the present disclosure, the processor is configured to determine the corresponding power distribution of the at least one laser beam based on the scan timing. Advantageously, for instance, the maximum individual power in time can be got.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to change the corresponding location of the observation area to determine the corresponding power distribution of the laser beam based on the scan timing. Advantageously, for example, scan timing can comprise absolute time as well as relative to the corresponding repetition rate.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to determine a time-based power distribution of different and/or subsequent scan frames. Advantageously, for instance, the time-based power distribution can comprise time relative to the corresponding repetition rate, which can analogously apply for the following implementation form.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to change the corresponding location of the observation area, especially across the scan area, to determine a time-based power distribution of different and/or subsequent scan frames.

According to a further implementation form of the first aspect of the present disclosure, the observation area is smaller than the scan area. Advantageously, for example, the observation area can be moved in an overlapping or non-overlapping manner to cover the scan area.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to use the time domain associated with the scan timing to determine a time-based scan pattern of the at least one laser beam for an entire or partial repetition. Advantageously, for instance, the corresponding device emitting the at least one laser beam can be characterized in a particularly accurate and efficient manner.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to provide the corresponding power of the at least one laser beam especially to a user. Advantageously, for example, the laser beam tester can comprise a display being in communication with the processor, wherein the display is configured to display the corresponding power of the at least one laser beam.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to provide a scan pattern analysis with respect to the at least one scan frame especially to a user. Advantageously, for instance, the laser beam tester can comprise a display being in communication with the processor, wherein the display is configured to display the scan pattern analysis.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to determine a frame rate with respect to the at least one scan frame. Advantageously, for example, it can efficiently be determined how long the corresponding full scan takes.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to determine a repetition rate, especially a maximum repetition rate, for adjacent laser beams. Advantageously, for instance, it can efficiently be determined how fast the corresponding laser beams or pulses, respectively, occur.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to determine average power for a particular time window with respect to the at least one laser beam. Advantageously, for example, eye safety requirements can be checked or achieved, respectively, in a reliable manner.

According to a further implementation form of the first aspect of the present disclosure, the scan timing comprises or is repetition frequency and/or phase with respect to the at least one laser beam. In addition to this or as an alternative, the processor is configured to associate the corresponding time domain of the laser beam tester with the corresponding location and/or angle of the at least one laser beam. Advantageously, for instance, efficiency can be increased.

According to a further implementation form of the first aspect of the present disclosure, the laser beam tester further comprises an optical transmitter being in communication with the processor, wherein the optical transmitter is configured to transmit a return light signal in response to the at least one laser beam. Advantageously, for example, a lidar target can be emulated or simulated, respectively.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to manipulate the return light signal on the corresponding time basis to map a response to a particular location. Advantageously for instance, a lot of additional resolution can be given.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to manipulate the return light signal to shape at least one return object. Advantageously, for example, the at least one return object can comprise or be a lidar target.

According to a further implementation form of the first aspect of the present disclosure, the processor is configured to increase contrast of the return light signal especially with the aid of spatial and/or temporal filtering. Advantageously, for instance, a lidar sensor can be tested in a particularly accurate and efficient manner.

According to a second aspect of the present disclosure, a system is provided. Said system comprises the laser beam tester according to the first aspect of the present disclosure or any of its implementation forms, respectively, and a laser beam emitting device configured to provide a repetitive scan of at least one laser beam in a scan area based on at least one scan frame, especially a lidar device or a lidar sensor. In this context, the laser beam tester is configured to determine laser beam timing and location with respect to the repetitive scan of the at least one laser beam. Advantageously, laser beam timing and location can be determined in a particularly accurate and efficient manner.

According to an implementation form of the second aspect of the present disclosure, the processor of the laser beam tester is configured to set a frame trigger of the laser beam tester such that the frame trigger of the laser beam tester has a constant offset to a frame start of the laser beam emitting device. Advantageously, for instance, a global frame trigger can be realized.

According to a third aspect of the present disclosure, a method, especially using the laser beam tester according to the first aspect of the present disclosure or any of its implementation forms, respectively, for laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame is provided. Said method comprises the steps of receiving the at least one laser beam in an observation area, determining the corresponding scan timing of the at least one laser beam, and associating the corresponding time domain, especially of the laser beam tester, with the scan timing of the at least one laser beam. Advantageously, laser beam timing and location can be determined in a particularly accurate and efficient manner.

Firstly, with respect to, a laser beam testerfor laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame is illustrated. Exemplarily, said at least one laser beam is emitted by a laser beam emitting device. Said laser beam emitting devicemay especially be a lidar device or a lidar sensor.

For the sake of completeness, it is noted that saidfurther depicts a systemcomprising said laser beam testerand said laser beam emitting device. In this context, as indicated above, the laser beam emitting deviceis configured to provide a repetitive scan of at least one laser beam in a scan area based on at least one scan frame, and the laser beam testeris configured to determine laser beam timing and location with respect to the repetitive scan of the at least one laser beam.

As it can further be seen from, the laser beam testercomprises an optical receiverconfigured to receive the at least one laser beam in an observation area, and a processorbeing in communication with the optical receiver. The processoris configured to determine the corresponding scan timing of the at least one laser beam. In addition to this, the processoris configured to associate the corresponding time domain of the laser beam testerwith the scan timing of the at least one laser beam.

Again, with respect to the above-mentioned system, it is noted that it might be particularly advantageous if the processorof the laser beam testeris configured to set a frame trigger of the laser beam testersuch that the frame trigger of the laser beam testerhas a constant offset to a frame start of the laser beam emitting device.

With respect to the above-mentioned scan timing, it is noted that it might be particularly advantageous if on the basis of the scan timing, a heartbeat or heartbeat signal, respectively, is given. It is further noted that said heartbeat or heartbeat signal, respectively, may especially be understood as a signal that is synchronized with the frame rate of the laser beam emitting deviceand comes either at each start of a corresponding frame or with a constant delay to the start of the frame.

With respect to the above-mentioned processor, it is noted that it might be particularly advantageous if the processoris configured to determine the corresponding power distribution of the at least one laser beam based on the scan timing.

Furthermore, it might be particularly advantageous if the processoris configured to change the corresponding location of the observation area to determine the corresponding power distribution of the laser beam based on the scan timing.

Moreover, it might be particularly advantageous if the processoris configured to determine a time-based power distribution of different and/or subsequent scan frames.

It is further noted that it might be particularly advantageous if the processoris configured to change the corresponding location of the observation area, especially across the scan area, to determine a time-based power distribution of different and/or subsequent scan frames.

With respect to the above-mentioned scan area and the above-mentioned observation area, it is noted that it might be particularly advantageous if the observation area is smaller than the scan area.

Again, with respect to the above-mentioned processor, it is noted that it might be particularly advantageous if the processoris configured to use the time domain associated with the scan timing to determine a time-based scan pattern of the at least one laser beam for an entire repetition.

Furthermore, it might be particularly advantageous if the processoris configured to provide the corresponding power of the at least one laser beam especially to a user.

Moreover, it might be particularly advantageous if the processoris configured to provide a scan pattern analysis with respect to the at least one scan frame especially to a user.

It is further noted that it might be particularly advantageous if the processoris configured to determine a frame rate with respect to the at least one scan frame.

Furthermore, it is noted that it might be particularly advantageous if the processoris configured to determine a maximum repetition rate for adjacent laser beams.

Moreover, it is noted that it might be particularly advantageous if the processoris configured to determine average power for a particular time window with respect to the at least one laser beam.

Again, with respect to the above-mentioned scan timing, it is noted that it might be particularly advantageous if the scan timing comprises or is repetition frequency and/or phase with respect to the at least one laser beam.

It is further noted that it might be particularly advantageous if the processoris configured to associate the corresponding time domain of the laser beam tester with the corresponding location and/or angle of the at least one laser beam.

Now, with respect to, a laser beam testerfor laser beam timing and location determination with respect to a repetitive scan of at least one laser beam in a scan area based on at least one scan frame is illustrated. Exemplarily, said at least one laser beam is emitted by a laser beam emitting device. Said laser beam emitting devicemay especially be a lidar device or a lidar sensor.

For the sake of completeness, it is noted that saidfurther depicts a systemcomprising said laser beam testerand said laser beam emitting device. In this context, as indicated above, the laser beam emitting deviceis configured to provide a repetitive scan of at least one laser beam in a scan area based on at least one scan frame, and the laser beam testeris configured to determine laser beam timing and location with respect to the repetitive scan of the at least one laser beam.

As it can further be seen from, the laser beam testercomprises an optical receiverconfigured to receive the at least one laser beam in an observation area, a processorbeing in communication with the optical receiver, and an optical transmitterbeing in communication with the processor. The processoris configured to determine the corresponding scan timing of the at least one laser beam. In addition to this, the processoris configured to associate the corresponding time domain of the laser beam testerwith the scan timing of the at least one laser beam. Further additionally, the optical transmitteris configured to transmit a return light signal, exemplarily to the laser beam emitting device, in response to the at least one laser beam.

It is noted that the explanations above regarding the laser beam testercan analogously apply for the laser beam tester, and vice versa. The explanations above regarding the optical receivercan analogously apply for the optical receiver, and vice versa. Furthermore, the explanations above regarding the processorcan analogously apply for the processor, and vice versa. Moreover, the explanations above regarding the laser beam emitting devicecan analogously apply for the laser beam emitting device, and vice versa.

Again, with respect to the above-mentioned system, it is noted that it might be particularly advantageous if the processorof the laser beam testeris configured to set a frame trigger of the laser beam testersuch that the frame trigger of the laser beam testerhas a constant offset to a frame start of the laser beam emitting device. It is further noted that the explanations above regarding the systemcan analogously apply for the system, and vice versa.

With respect to the above-mentioned processor, it is noted that it might be particularly advantageous if the processoris configured to manipulate the return light signal on the corresponding time basis to map a response to a particular location.